1. Field of the Invention
The present invention relates generally to crop harvesting machines, such as windrowers or windrower-conditioners. More particularly, the present invention concerns the long spanning augers for centralizing and evenly distributing severed crop as it moves rearwardly to the relatively shorter conditioning rolls, and supports for supporting the long spanning augers between their respective opposite ends without interfering with the flow of crop between the augers.
2. Discussion of the Prior Art
Harvesting machines, which are variously referred to as windrowers or windrower-conditioners, have traditionally employed a cutter for severing a swath of crop having a width generally equal to that of the machine. An exemplary showing of a windrower-conditioner is made in U.S. Pat. No. 4,637,201, entitled WIDE-CUT WINDROWER-CONDITIONER HAVING UNIFORM CROP DISTRIBUTION AND CONDITIONING, assigned of record to the assignee of the present invention. Of course, it would be desirable to decrease the time it takes a farmer to harvest a field with the harvesting machine. If the cutter of the harvester is widened so that a wider swath of crop is taken by the machine as it moves across a field, the farmer can make relatively fewer passes across a field and thereby harvest a field in less time, assuming the machine has the capacity to condition and windrow the additional crop severed by the wide cutter. However, conventional harvesting machines have several limitations which restrict increasing the width of cut taken by the machine.
For example, the severed crop must be converged centrally to form a relatively narrow windrow to be picked up later by another machine, such as a hay baler or wagon. The windrow width must not be larger than the width of pickups on these machines, or the farmer will have to make more than one pass across the field to pick up a single windrow. Accordingly, the windrower must include structure for converging the crop from the wide swath taken by the cutter to the narrow windrow deposited on the ground. Some machines simply include rearwardly converging windrow-forming shields located behind the cutter, which are obviously ineffective in forming a uniform windrow when a wide cut is taken by the machine--the sides of the windrow tend to be more dense than the center when only shields are utilized. The demand for wider machines has resulted in the development of powered mechanism for positively feeding the outboard crop centrally; such powered mechanism normally comprising one or more laterally extending augers. As will subsequently be described, there have heretofore been limitations on the length of such augers, thereby placing a restriction on the corresponding width of the machine.
Moreover, when the harvesting machine also performs the function of conditioning the crop, the crop is traditionally passed between a pair of laterally extending, vertically spaced conditioning rolls located behind the converging mechanism. It has been determined that the crop must be uniformly fed to the conditioning rolls, or the crop is unevenly conditioned and consequently dries at irregular rates and the rolls may become damaged. Further, the conditioning rolls on a wide-cut machine are desirably shorter than the cutting width for numerous reasons well appreciated by those of ordinary skill in the art. For example, the conditioned crop is preferably deposited evenly on the ground so as to facilitate uniform drying, and accordingly, it is desirable to reduce or eliminate the need to converge the crop once it has been conditioned.
As mentioned above, one type of mechanism for converging the crop from the cutter to the conditioning rolls comprises a center-gathering auger having a length substantially equal to the cutting width. A pair of bearing assemblies traditionally serve to support the auger at its opposite ends on the header framework. Helical vanes extending inwardly from the opposite ends converge the severed crop centrally from areas located laterally outboard of the conditioning rolls, when the auger is rotated. At first glance, it seems that the length of the auger need only be extended to accommodate a relatively wider cutter. However, as the center-gathering auger is extended, the weight of the auger and corresponding operational loads tend to place undue wear and stress on the bearing assemblies. Moreover, the extended auger may begin to sag between its opposite ends, which could interfere with the operation of the auger or other components of the header and could cause serious damage to the header. Furthermore, it is important that the structure for supporting the auger does not interfere with the flow of crop from the cutter to the conditioning rolls.
In some instances, the harvester may also include a second upwardly spaced auger for evenly spreading the crop across the width of the conditioning rolls so that the crop is uniformly conditioned. Indeed, extending the length of the second auger presents the same problems as those noted above with respect to the center-gathering auger. Particularly, it is extremely important that the structure for rotatably supporting the augers on the header framework does not project into the relatively narrow throat defined between the augers.